Carcinoma medular esporádico de tiroides / Sporadic Medullary Thyroid Carcinoma

Introducción: El carcinoma medular de tiroides, representa aproximadamente entre el 5 - 10 por ciento de todos los carcinomas tiroideos, aparece con más frecuencia entre los 25 y 60 años y en el sexo femenino. Se distinguen dos tipos: el esporádico (no hereditario) y el familiar (hereditario). La localización más frecuente es la unión del tercio superior de lóbulo tiroideo con el tercio medio, que es la zona de mayor concentración de células C. Objetivo: Presentar el caso de paciente masculino operado de carcinoma medular de tiroides, tipo esporádico, en la provincia de Cienfuegos. Caso clínico: Paciente masculino de 60 años de edad, piel blanca, que acudió a la consulta; refiere aumento de volumen del cuello acompañado de disfonía y disfagia a los alimentos sólidos. Al examen físico se constató la presencia del nódulo tiroideo. Se le realizó ultrasonido que corrobora la presencia de un nódulo en el lóbulo derecho del tiroides. La biopsia por aspiración con aguja fina informó el nódulo como sospechoso de malignidad. Se le realizó tiroidectomía total, informándose por la biopsia por parafina de la pieza como un carcinoma medular del tiroides. En la actualidad lleva 6 meses de operado con evolución favorable. Conclusiones: El carcinoma medular de tiroides constituye una entidad rara y agresiva más frecuente en los pacientes mayores de 45 años, cuyo tratamiento de elección es la cirugía(AU)

Introduction: Medullary thyroid carcinoma accounts for approximately 5-10 percent of all thyroid carcinomas. It appears more frequently at ages 25-60 years and in females. Two types are distinguished: sporadic (nonhereditary) and familial (hereditary). The most common location is the union of the upper third of the thyroid lobe to the middle third, the area with the highest concentration of C cells. Objective: To present the case of a male patient operated on for medullary thyroid carcinoma, of sporadic type, in the Cienfuegos Province. Clinical case: A 60-year-old male patient of white skin attended consultation. He reported an increase in neck volume accompanied by dysphonia and dysphagia for solid food. The physical examination revealed the presence of the thyroid nodule. Ultrasound was performed, which confirmed the presence of a nodule in the right lobe of the thyroid. Fine needle aspiration biopsy reported the nodule as suspicious for malignancy. A total thyroidectomy was performed, after which, paraffin biopsy of the specimen permitted to report a medullary carcinoma of the thyroid. At present, he has been operating for six months, with favorable evolution. Conclusions: Medullary thyroid carcinoma is a rare and aggressive entity, more frequent in patients over 45 years of age, whose treatment of choice is surgery(AU)

Neoplasia endócrina múltipla tipo 2A: relato de caso / Multiple endocrine neoplasia type 2A: a case report / Neoplasia endocrina múltiple tipo 2A: reporte de caso

As neoplasias endócrinas múltiplas (NEM) são síndromes genéticas autossômicas dominantes implicadas no desenvolvimento de neoplasias benignas ou malignas, envolvendo ao menos duas glândulas endócrinas. Entre seus subtipos, está a NEM2A, que consiste em carcinoma medular de tireoide (CMT), feocromocitoma e hiperparatireoidismo. Este texto apresente o relato de caso de um paciente de 40 anos, previamente hígido, que passou a apresentar episódios de cefaleia associada a sudorese profusa, vômitos e taquicardia. Evoluiu com distensão abdominal intensa após alimentação por via oral, perda ponderal, desnutrição, astenia, obstipação, humor deprimido e picos pressóricos. Exames laboratoriais evidenciaram alterações dos hormônios tireoidianos, PTH e hormônios da adrenal. Foi levantada a suspeita clínica de NEM2A, posteriormente corroborada pelos diagnósticos anatomopatológicos de feocromocitoma e CMT, associados à presença de hiperparatireoidismo. Foi possível concluir que, a despeito de sua baixa prevalência na população geral, a NEM é uma síndrome clínica de grande relevância, tendo em vista os impactos para os pacientes e famílias acometidas. Dessa forma, é necessário que os profissionais de saúde tenham conhecimento acerca da síndrome e que o Sistema Único de Saúde (SUS) esteja apto a assistir aos pacientes portadores de NEM, possibilitando diagnóstico precoce e tratamento adequado.

Multiple endocrine neoplasias (MEN) are dominant autosomal genetic syndromes involved in the development of benign or malignant tumors in at least two endocrine glands. MEN2A is one of its subtypes, which consists of medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism. This study reports the case of a healthy 40-year-old male patient presenting with episodes of headache associated with profuse sweating, vomiting, and tachycardia. The patient evolved with severe abdominal distension after oral feeding, weight loss, malnutrition, asthenia, constipation, depressed mood, and pressure peaks. Laboratory tests showed abnormalities in thyroid, parathyroid (PTH), and adrenal hormones ­ thus raising the hypothesis of MEN2A, which was later corroborated by the histological diagnosis of pheochromocytoma and MTC, associated with hyperparathyroidism. The results indicate that, despite its low prevalence in the general population, MEN has a great impact on affected patients and families, thus being a relevant clinical syndrome. For enabling early diagnosis and adequate treatment, health professionals must be familiarized with such a condition, and the Brazilian Unified Health System (SUS) must be able to assist affected patients.

Las neoplasias endocrinas múltiples (NEM) son síndromes genéticos autosómicos dominantes involucrados en el desarrollo de neoplasias benignas o malignas, que afectan al menos dos glándulas endocrinas. Entre sus subtipos se encuentra NEM2A, que consiste en carcinoma medular de tiroides (CMT), feocromocitoma e hiperparatiroidismo. Este es un reporte de caso de un paciente de 40 años de edad, previamente sano, que comenzó a presentar episodios de cefalea asociada a sudoración profusa, vómitos y taquicardia. Evolucionó con distensión abdominal severa después de alimentarse, pérdida de peso, desnutrición, astenia, estreñimiento, estado de ánimo deprimido y picos de presión. Las pruebas de laboratorio mostraron alteraciones en las hormonas tiroideas, PTH y hormonas suprarrenales. Se planteó la hipótesis de MEN2A, posteriormente corroborada por el diagnóstico anatomopatológico de feocromocitoma y CMT, asociado a hiperparatiroidismo. Se pudo concluir que, a pesar de su baja prevalencia en la población general, el NEM es un síndrome clínico de gran relevancia, dado el impacto que tiene en los pacientes y familiares afectados. Por tanto, es necesario que los profesionales sanitarios tengan conocimiento sobre el síndrome y que el Sistema Único de Salud (SUS) sea capaz de asistir a los pacientes con NEM, posibilitándoles diagnóstico precoz y tratamiento adecuado.

Rare complications of multikinase inhibitor treatment

ABSTRACT Objective: The advent of multikinase inhibitor (MKI) therapy has led to a radical change in the treatment of patients with advanced thyroid carcinoma. The aim of this manuscript is to communicate rare adverse events that occurred in less than 5% of patients in clinical trials in a subset of patients treated in our hospital. Subjects and methods: Out of 760 patients with thyroid cancer followed up with in our Division of Endocrinology, 29 (3.8%) received treatment with MKIs. The median age at diagnosis of these patients was 53 years (range 20-70), and 75.9% of them were women. Sorafenib was prescribed as first-line treatment to 23 patients with differentiated thyroid cancer and as second-line treatment to one patient with advanced medullary thyroid cancer (MTC). Vandetanib was indicated as first-line treatment in 6 patients with MTC and lenvatinib as second-line treatment in two patients with progressive disease under sorafenib treatment. Results: During the follow-up of treatment (mean 13.7 ± 7 months, median 12 months, range 6-32), 5/29 (17.2%) patients presented rare adverse events. These rare adverse effects were: heart failure, thrombocytopenia, and squamous cell carcinoma during sorafenib therapy and squamous cell carcinoma and oophoritis with intestinal perforation during vandetanib treatment. Conclusions: About 3 to 5 years after the approval of MKI therapy, we learned that MKIs usually lead to adverse effects in the majority of patients. Although most of them are manageable, we still need to be aware of potentially serious and rare or unreported adverse effects that can be life-threatening.

Estudio patológico intraoperatorio en la cirugía tiroidea: ¿cuánto contribuye a la estrategia quirúrgica? / Intraoperative pathologic evaluation in thyroid surgery: how much does it contribute to surgical strategy?

Antecedentes: el papel del estudio patológico intraoperatorio (EPI) en cirugía tiroidea ha sido discutido largamente y es todavía motivo de controversia. Objetivo: estimar los resultados del EPI en el diagnóstico de malignidad, su relación con la biopsia por punción-aspiración preoperatoria con aguja fina (PAAF) y el estudio patológico diferido (EPD), así como su contribución al cambio en la estrategia quirúrgica en cirugía tiroidea. Material y métodos: revisión retrospectiva de las historias clínicas de 773 pacientes operados por patología tiroidea entre enero de 2014 y diciembre de 2015. En todos se efectuó EPI y EPD; a 686 (89%) pacientes también se les efectuó la biopsia por PAAF preoperatoria. Resultados: los resultados del EPI fueron benigno en 215 pacientes (27,8%), maligno en 419 (54,2%) y no definitivo en 139 (18,0%). Cuando estos resultados fueron comparados con la EPD se encontraron 19 casos (8,8%) de falsos negativos y 4 (0,95%) de falsos positivos. Considerando solo los resultados definitivos, el EPI tuvo sensibilidad 95%, especificidad 98%, valor predictivo positivo 99%, valor predictivo negativo 91% y exactitud 91%. Cuando se comparó el EPI con la PAAF preoperatoria, los valores de sensibilidad más bajos (44%) correspondieron a las categorías de Bethesda III y IV. El EPI influyó en la estrategia quirúrgica en 95 pacientes (12,28%): en 53 (6,8%), la hemitiroidectomía cambió a tiroidectomía total; en 37 (4,8%), el diagnóstico de metástasis ganglionares permitió realizar un vaciamiento modificado de cuello, y en 5 (0,6%) ocurrieron ambas situaciones. Conclusión: el EPI tuvo altos valores de utilidad diagnóstica cuando se compararon con el EPD. También se correlacionó con la PAAF preoperatoria, pero tuvo menos utilidad en las categorías Bethesda III y IV. El EPI contribuyó a cambiar la decisión de técnica quirúrgica en un grupo de pacientes y evitar una segunda operación.

Background: the role of intraoperative pathologic evaluation (IPE) in thyroid surgery has largely been discussed and it is still controversial. Objective: to estimate the results of IPE in diagnosis of malignancy, its correlation with preoperative fine needle aspiration (FNA) biopsy and permanent pathologic evaluation (PPE), and its contribution to change surgical strategy in thyroid surgery. Materials and methods: retrospective chart review of 773 patients operated on for thyroid disease between January 2014 and December 2015. All patients underwent IPE and PPE; 686 (89%) patients had also preoperative FNA biopsy. Results: IPE resulted benign in 215 patients (27.8%), malignant in 419 (54.2%) and non definitive in 139 (18.0%). When these results were compared with PPE, 19 cases were false negative (8.8%) and 4 false positive (0.95). Considering only definitive results, IPE had sensitivity 95%, specificity 98%, positive predictive value 99%, negative predictive value 91% and accuracy 91%. When IPE was compared with preoperative FNA biopsy, lowest values of sensitivity (44%) corresponded with Bethesda categories III and IV. IPE influenced surgical strategy in 95 patients (12.28%): in 53 (6.8%) hemithyroidectomy changed to total thyroidectomy, in 37 (4.8%) lymph node metastases diagnosis allowed to perform modified neck dissection, and in 5 (0.6%) both situations occurred. Conclusion: IPE had high values of diagnostic utility when compared with PPE. It also correlated with preoperative FNA biopsy, but had less utility in Bethesda categories III and IV. IPE contributed to change surgical technical decision in a subset of patients and avoid a second operation.

Cirugía profiláctica en cáncer medular de tiroides hereditario / Prophylactic surgery in hereditary medullary thyroid cancer

Introducción: Se estima que del total de los cánceres, el 5-10% tendría una base genética. Actualmente es posible identificar a los individuos con predisposición genética en algunos cánceres como manera de intervenir precozmente en el desarrollo de esta enfermedad. Objetivos: Evaluar la utilidad de la cirugía profiláctica en el cáncer medular de tiroides hereditario. Material y métodos: Este trabajo es una revisión de literatura de diferentes estudios extraídos de bibliotecas electrónicas como Scientific Electronic Library Online (SciELO), MedLine-PubMed y UpToDate, mediante la construcción de preguntas clínicas y términos MeSH enfocados principalmente en la búsqueda específica de información sobre el cáncer medular de tiroides hereditario. Resultados: Los estudios revisados demuestran que la tiroidectomía profiláctica con resección linfática cervical representa el único tratamiento eficaz en el caso del cáncer medular de tiroides hereditario. Conclusiones: La cirugía profiláctica ha demostrado una importante disminución del riesgo de cáncer de tiroides y se considera una conducta de rigor en portadores del gen RET en el cáncer medular de tiroides.

Introduction: Approximately 5-10% of global cancer has a genetic base. Nowadays it is possible to identify those who have a genetic predisposition for some cancers, so they can be treated in short term. Objectives: Evaluate how useful is prophylactic surgery on hereditary Medullary Thyroid Cancer. Materials and methods: This investigation is a literature review of different research papers from electronic databases such as Scientific Electronic Library Online (SciELO), MedLine-PubMed and UpToDate. The research was made with clinical queries and MeSH terms, specially focused on hereditary Medullary Thyroid Cancer. Results: This research shows that prophylactic Thyroidectomy with cervical lymph node resection is the only effective and curative treatment for hereditary Medullary Thyroid Cancer. Conclusions: Prophylactic surgery has proof an important role decreasing the risk on Hereditary Thyroid cancer Syndrome and in RET carriers surgery is considered a must.

Guía práctica para el manejo de efectos adversos por inhibidores multicinasas (sorafenib y vandetanib) en pacientes con cáncer de tiroides avanzado / Practice guidelines for the management of adverse effects due to multikinase inhibitors (sorafenib and vandetanib) in patients with advanced thyroid cancer

El advenimiento de la terapia con inhibidores multicinasas (IMK) representó un cambio radical en el tratamiento de pacientes con carcinoma avanzado de tiroides. Hasta la fecha, 2 fármacos se encuentran aprobados por la Asociación Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT) en Argentina: sorafenib, para pacientes con carcinoma diferenciado de tiroides radiorresistente, y vandetanib, para aquellos con carcinoma medular de tiroides (enfermedad progresiva y/o sintomática). Los estudios de fase III han demostrado que estos fármacos aumentan significativamente la supervivencia libre de progresión en este grupo de pacientes. Si bien tienen una indicación precisa, su manejo requiere de un equipo multidisciplinario en contacto estrecho con un paciente involucrado en su tratamiento. Los efectos adversos de sorafenib y vandetanib son frecuentes, sin embargo, muchos de ellos disminuyen con el tiempo y la mayoría puede manejarse a menudo sin disminuir la dosis ni suspender el fármaco. El conocimiento del correcto manejo de los efectos adversos por parte del equipo tratante constituye una herramienta fundamental para poder educar al paciente y, consecuentemente, poder prevenirlos o minimizarlos, y de esta manera evitar complicaciones severas. El objetivo de esta publicación es brindar una guía para el diagnóstico y tratamiento de los efectos adversos de estos IMK y, por otro lado, presentar la iniciativa del Hospital de Clínicas de la Universidad de Buenos Aires en cuanto a la implementación de la misma.

The advent of multikinase inhibitors therapy has led to a radical change in the treatment of patients with advanced thyroid carcinoma. The ANMAT (the Argentinian regulatory health agency) has currently approved sorafenib for patients with radioiodine resistant differentiated thyroid carcinoma, and vandetanib for patients with medullary thyroid carcinoma (progressive and/or symptomatic disease). It has been demonstrated by phase III clinical trials that these drugs improve progression free survival in this group of patients. Although they have a precise indication, an interdisciplinary team in close contact with a committed patient, are required for their effective management. The adverse events of these drugs are common, but many of them may ameliorate over time, and most of them are manageable, even without the need for dose reduction or drug withdrawal. Knowledge of the correct management of the adverse events is a fundamental tool for the medical team and for the patient to prevent or minimise them, to avoid serious complications and to obtain better patient compliance. The primary objective of this article is to provide a guideline for the diagnosis and treatment of the adverse events produced by the multikinase inhibitors, and to present the initiative of the Hospital de Clinicas in order to implement these guidelines.

Uso de inhibidores de tirosina quinasa en carcinoma medular de tiroides. Experiencia Institucional / Use of tyrosine kinase inhibitors in medullary thyroid carcinoma. Institutional Experience

El cáncer medular de tiroides (CMT) correspondeal 5% de los tumores de la glándula tiroides. El único tratamiento curativo es la cirugía. En pacientes con compromiso locorregional o a distancia, la enfermedad puede evolucionar en forma indolente o bien con una rápida progresión de síntomas, requiriendo tratamiento sistémico. Si bien el CMT se caracteriza por tener escasa respuesta a la quimioterapia (QT), la evidencia actual en estudios aleatorizados demostró que los inhibidores de tirosina quinasa (ITQ) han demostrado beneficio en supervivencia libre de progresión (SLP). Se analizaron 6 pacientes con un seguimiento mediano de 29 meses. Todos presentaron más de dos sitios metastásicos. Dos requirieron tratamientos locorregionales (quimioembolización y RT). Los ITQ más utilizados fueron: vandetanib (3), sorafenib (2) y sunitinib (1). Un 50% inició tratamiento con dosis plenas y 3 requirieron reducción de dosis debido a toxicidad G3-G4. El intervalo libre de progresión (ILP) mediano, luego del inicio con ITQ, fue de 4.1 meses (AU)

Medullary thyroid cancer (CMT) accounts for 5% of thyroid tumors. The only curative treatment is surgery. In patients with locally or distal involvement, the disease may evolve indolently or with rapid progression of symptoms, requiring systemic treatment. Although CMT is characterized by a poor response to chemotherapy, current evidence in randomized trials has shown that tyrosine kinase inhibitors (ITKs) have demonstrated benefit in progressionfree survival. Six patients with a median follow-up of 29 months were analyzed. All had more than two metastatic sites. Two patients required locoregional treatments (chemoembolization and radio therapy). The most commonly used ITKs were: vandetanib (3), sorafenib (2) and sunitinib (1). The 50% initiated treatment with full dose and 3 required reduction of the dose due to G3- G4 toxicity. The median progression-free interval after initiation with ITK was 4.1 months (AU)

Diagnóstico, tratamento e seguimento do carcinoma medular de tireoide: recomendações do Departamento de Tireoide da Sociedade Brasileira de Endocrinologia e Metabologia / Diagnosis, treatment, and follow-up of medullary thyroid carcinoma: recommendations by the Thyroid Department of the Brazilian Society of Endocrinology and Metabolism

Introdução O carcinoma medular de tireoide (CMT) origina-se das células parafoliculares da tireoide e corresponde a 3-4% das neoplasias malignas da glândula. Aproximadamente 25% dos casos de CMT são hereditários e decorrentes de mutações ativadoras no proto-oncogene RET (REarranged during Transfection). O CMT é uma neoplasia de curso indolente, com taxas de sobrevida dependentes do estádio tumoral ao diagnóstico. Este artigo descreve diretrizes baseadas em evidências clínicas para o diagnóstico, tratamento e seguimento do CMT. Objetivo O presente consenso, elaborado por especialistas brasileiros e patrocinado pelo Departamento de Tireoide da Sociedade Brasileira de Endocrinologia e Metabologia, visa abordar o diagnóstico, tratamento e seguimento dos pacientes com CMT, de acordo com as evidências mais recentes da literatura. Materiais e métodos: Após estruturação das questões clínicas, foi realizada busca das evidências disponíveis na literatura, inicialmente na base de dados do MedLine-PubMed e posteriormente nas bases Embase e SciELO – Lilacs. A força das evidências, avaliada pelo sistema de classificação de Oxford, foi estabelecida a partir do desenho de estudo utilizado, considerando-se a melhor evidência disponível para cada questão. Resultados Foram definidas 11 questões sobre o diagnóstico, 8 sobre o tratamento cirúrgico e 13 questões abordando o seguimento do CMT, totalizando 32 recomendações. Como um todo, o artigo aborda o diagnóstico clínico e molecular, o tratamento cirúrgico inicial, o manejo pós-operatório e as opções terapêuticas para a doença metastática. Conclusões O diagnóstico de CMT deve ser suspeitado na presença de nódulo tireoidiano e história ...

Introduction Medullary thyroid carcinoma (MTC) originates in the thyroid parafollicular cells and represents 3-4% of the malignant neoplasms that affect this gland. Approximately 25% of these cases are hereditary due to activating mutations in the REarranged during Transfection (RET) proto-oncogene. The course of MTC is indolent, and survival rates depend on the tumor stage at diagnosis. The present article describes clinical evidence-based guidelines for the diagnosis, treatment, and follow-up of MTC. Objective The aim of the consensus described herein, which was elaborated by Brazilian experts and sponsored by the Thyroid Department of the Brazilian Society of Endocrinology and Metabolism, was to discuss the diagnosis, treatment, and follow-up of individuals with MTC in accordance with the latest evidence reported in the literature. Materials and methods: After clinical questions were elaborated, the available literature was initially surveyed for evidence in the MedLine-PubMed database, followed by the Embase and Scientific Electronic Library Online/Latin American and Caribbean Health Science Literature (SciELO/Lilacs) databases. The strength of evidence was assessed according to the Oxford classification of evidence levels, which is based on study design, and the best evidence available for each question was selected. Results Eleven questions corresponded to MTC diagnosis, 8 corresponded to its surgical treatment, and 13 corresponded to follow-up, for a total of 32 recommendations. The present article discusses the clinical and molecular diagnosis, initial surgical treatment, and postoperative management of MTC, as well as the therapeutic options for metastatic disease. Conclusions 7 .

Cáncer medular de tiroides: Experiencia quirúrgica en 10 años / Medullary thyroid cancer: Review of 28 patients

Background: Medullary thyroid cancer (MTC) represents approximately 5% of all thyroid cancers. Surgery is the only curative treatment, which includes total thyroidectomy and in most cases, neck dissection. Aim: To report our 10-year experience with surgical treatment of MTC. Material and Methods: Review of medical records and pathology reports of a university hospital. We retrieved data from 28 patients aged 47.2 ± 16 years (21 women) operated for a MTC treated between June 2002 and June 2012. Results: In 20 patients, MTC was diagnosed in the preoperative period. Total thyroidectomy was performed in all cases and included a neck dissection in 24 patients. Median follow-up was 48 (2-120) months. Twenty-five patients (89.2%) achieved complete remission of the disease and three had disease recurrence. There were no deaths during the follow up. Conclusions: The diagnosis of MTC is mainly based on cytology. Total thyroidectomy with neck dissection is the treatment of choice. An early-stage diagnosis is associated with low rates of recurrence and absence of mortality.

Usefulness of preoperative serum calcitonin in patients with nodular thyroid disease without suspicious history or cytology for medullary thyroid carcinoma / Utilidade da calcitonina sérica pré-operatória em pacientes com doença nodular tireoidiana sem história ou citologia suspeitas para carcinoma medular de tireoide

OBJECTIVE: To evaluate the usefulness of preoperative serum calcitonin (sCT) in patients with nodular disease without suspicion of medullary thyroid carcinoma (MTC) in history or cytology. PATIENTS AND METHODS: sCT was measured before thyroidectomy in 494 patients with nodular disease who had no family history of MTC or multiple endocrine neoplasia type 2, and no cytological suspicion of MTC. RESULTS: Basal sCT was < 10 ng/mL in 482 patients and none of them had MTC. One patient with basal sCT > 100 pg/mL had MTC. Among the 11 patients with basal sCT between 10 and 100 pg/mL, MTC was diagnosed in only one. The two patients with MTC were submitted to total thyroidectomy, combined with elective lymph node dissection indicated exclusively based on hypercalcitoninemia, and sCT was undetectable after six months. CONCLUSIONS: Preoperative sCT is useful for the detection of sporadic MTC in patients with nodular disease, even in the absence of suspicious history or cytology.

OBJETIVO: Avaliar a utilidade da calcitonina sérica (sCT) pré-operatória em pacientes com doença nodular sem suspeita de carcinoma medular de tireoide (CMT) pela história e citologia. PACIENTES E MÉTODOS: Antes da tireoidectomia, sCT foi dosada em 494 pacientes com doença nodular, sem história familiar de CMT ou neoplasia endócrina múltipla tipo 2 e sem citologia suspeita para CMT. RESULTADOS: sCT basal foi < 10 ng/ml em 482 pacientes e nenhum possuía CMT. Um paciente com sCT basal > 100 pg/ml realmente possuía CMT. Dos 11 pacientes com sCT basal entre 10 e 100 pg/ml, CMT foi diagnosticado em apenas um. Os dois pacientes com CMT foram submetidos à tireoidectomia total com dissecção eletiva de linfonodos, indicada exclusivamente pela hipercalcitoninemia, e após seis meses apresentaram sCT indetectável. CONCLUSÕES: Em pacientes com doença nodular, mesmo sem história ou citologia suspeitas, a sCT pré-operatória é útil para detecção do CMT esporádico.

Análise do gene CDKN1B/p27kip1 em pacientes com neoplasia endócrina múltipla tipo 2 / CDKN1B/p27kip1 gene analysis in patients with multiple endolcrine neopasia type 2 (MEN2)

INTRODUÇÃO: Na Neoplasia Endócrina Múltipla tipo 2 (NEM2), o desenvolvimento do Carcinoma Medular de Tireoide (CMT), Feocromocitoma (FEO) e Hiperparatireoidismo primário (HPT) está associado à mutações germinativas ativadoras no proto-oncogene RET. Casos de CMT esporádico podem apresentar mutações somáticas no RET (~40%). A variabilidade fenotípica observada em casos de CMT e FEO familiais associados à NEM2 indica o envolvimento de eventos genéticos adicionais que seriam responsáveis pelas diferenças clínicas observadas nos indivíduos afetados (idade de desenvolvimento, progressão e agressividade do tumor). Outras alterações genéticas no RET como duplas mutações, SNPs e haplótipos específicos podem influenciar na susceptibilidade, agressividade e modulação do fenótipo NEM2. Entretanto, os estudos de outros genes envolvidos no processo da tumorigênese NEM2 ainda estão em andamento. Recentemente foi mostrado que RET ativado controla a expressão de proteínas inibidoras do ciclo celular (p18 e p27). Mutações germinativas no gene p27 foram recentemente associadas à susceptibilidade de tumores neuroendócrinos e estão associadas à síndrome NEM4 (Neoplasia endócrina múltipla tipo 4). Mutações somáticas, inativadoras de p27, são raramente encontradas em vários tipos de tumores. Entretanto, diversos estudos documentaram que a redução na expressão e a sublocalização citoplamática de p27 são controladas por alterações pós-transducionais e/ou epigenéticas. OBJETIVOS: o estudo teve como objetivos avaliar a participação de genes, recentemente associados ao RET ativado, em tumores de pacientes com NEM2 e também verificar se polimorfismos no gene p27 estariam atuando como moduladores de fenótipo em uma grande família com NEM2. CASUÍTICA: foram analisadas 66 amostras tumorais advindas de 36 pacientes com diagnóstico clínico e genético de NEM2 e 28 indivíduos pertencentes a uma grande família com NEM2A-CMTF e mutação C620R no gene RET. MÉTODOS:...

INTRODUCTION: In Multiple Endocrine Neoplasia type 2 (MEN2) the development of medullary thyroid carcinoma (MTC), pheochromocytoma (PHEO) and primary hyperparathyroidism (HPT) are associated with activating germline mutations in RET proto-oncogene. Cases of sporadic MTC may have somatic RET mutations (~ 40%). The phenotypic variability observed in cases with familial MTC/MEN2 and PHEO/MEN2 indicates the probable involvement of additional genetic events that could be responsible for the clinical differences observed in the affected individuals (age development, progression and aggressiveness of the tumor). Other genetic alterations such as RET double mutations, SNPs and specific haplotypes may influence susceptibility, aggressiveness and MEN2 phenotype modulation. However, studies of other genes involved in the tumorigenesis of MEN2 are still in progress. Recently, it was shown that the activated RET controls the expression of cell cycle inhibitory proteins (p18 and p27). Germline mutations in the p27 gene have recently been associated with the susceptibility to neuroendocrine tumors and are associated with the MEN4 syndrome (Multiple endocrine neoplasia type 4). Somatic inactivating mutations p27 are rarely found in many types of tumors. However, several studies have documented that reduced expression and subcellular location of p27 is controlled by post-transductional changes and/or epigenetic factors. OBJECTIVES: This study aimed to evaluate the role of genes recently associated with RET activated in tumors from MEN2 patients and also check whether polymorphisms in the p27 gene would be acting as modulators of phenotype in a large MEN2 family. PATIENTS: We analyzed 66 tumor samples from 36 patients with clinical and genetic diagnosis of MEN2 and from 28 individuals belonging to a large family with FMTC/MEN2A and RET C620R mutation. METHODS: The analyses of somatic p27, p15, p18 and RET...

Narrowing the gap of personalized medicine in emerging countries: the case of multiple endocrine neoplasias in Brazil

The finished version of the human genome sequence was completed in 2003, and this event initiated a revolution in medical practice, which is usually referred to as the age of genomic or personalized medicine. Genomic medicine aims to be predictive, personalized, preventive, and also participative (4Ps). It offers a new approach to several pathological conditions, although its impact so far has been more evident in mendelian diseases. This article briefly reviews the potential advantages of this approach, and also some issues that may arise in the attempt to apply the accumulated knowledge from genomic medicine to clinical practice in emerging countries. The advantages of applying genomic medicine into clinical practice are obvious, enabling prediction, prevention, and early diagnosis and treatment of several genetic disorders. However, there are also some issues, such as those related to: (a) the need for approval of a law equivalent to the Genetic Information Nondiscrimination Act, which was approved in 2008 in the USA; (b) the need for private and public funding for genetics and genomics; (c) the need for development of innovative healthcare systems that may substantially cut costs (e.g. costs of periodic medical followup); (d) the need for new graduate and postgraduate curricula in which genomic medicine is emphasized; and (e) the need to adequately inform the population and possible consumers of genetic testing, with reference to the basic aspects of genomic medicine.

Multiple endocrine neoplasia: the Chilean experience

Multiple endocrine neoplasia (MEN) types 1 and 2 are genetic diseases that are inherited as autosomal traits. The major clinical manifestations of multiple endocrine neoplasia type 1 include the so-called "3 P's": parathyroid, pituitary, and pancreatic tumors, including gastroenteroneuroendocrine tumors. Genetic testing can be performed on patients and the potential carriers of the menin gene mutation, but the genotype-phenotype correlation in multiple endocrine neoplasia type 1 is less straightforward than multiple endocrine neoplasia type 2. Most likely, the main advantage of genetic testing in MEN1 is to exclude from further studies those who are negative for the genetic mutation if they belong to a family with a known history of MEN1. In Chile, we started with rearranged during transfection proto-oncogene genetic testing (MEN2) 15 years ago. We carried out a prophylactic total thyroidectomy to prevent medullary thyroid carcinoma in a three-year-old girl who presented with microscopic medullary thyroid carcinoma. More than 90% of the individuals who tested positive using a genetic test achieved a biochemical cure compared with only 27% of patients who receive a clinical diagnosis. Mutations are mainly located in exon 11; the most common is C634W, rather than C634R. Hypertensive crisis was the cause of death in three patients, and extensive distant metastases occurred in nine (including two patients with multiple endocrine neoplasia type 2B) of 14 patients. Earlier recognition of medullary thyroid carcinoma and the other features of the disease, especially pheochromocytoma, will improve the survival rate of patients with multiple endocrine neoplasia.

RET codon 609 mutations: a contribution for better clinical managing

Medullary thyroid carcinoma currently accounts for 5-8% of all thyroid cancers. The clinical course of this disease varies from extremely indolent tumors that can go unchanged for years to an extremely aggressive variant that is associated with a high mortality rate. As many as 75% of all medullary thyroid carcinomas are sporadic, with an average age at presentation reported as 60 years, and the remaining 25% are hereditary with an earlier age of presentation, ranging from 20 to 40 years. Germline RET proto-oncogene mutations are the genetic causes of multiple endocrine neoplasia type 2 and a strong genotype-phenotype correlation exists, particularly between a specific RET codon mutation and the (a) age-related onset and (b) thyroid tumor progression, from C-cell hyperplasia to medullary thyroid carcinoma and, ultimately, to nodal metastases. RET mutations predispose an individual to the development of medullary thyroid carcinomas and can also influence the individual response to RET protein receptor-targeted therapies. RET codon 609point mutations are rare genetic events belonging to the intermediate risk category for the onset of medullary thyroid carcinoma. A large genealogy resulting in a less aggressive form of medullary thyroid carcinoma is associated with the high penetrance of pheochromocytoma and has been reported in the literature. In this short review article, we comment on our previous report of a large multiple endocrine neoplasia type 2A kindred with the same Cys609Ser germline RET mutation in which, conversely, the syndrome was characterized by a slightly aggressive, highly penetrant form of medullary thyroid carcinoma that was associated with low penetrance of pheochromocytoma and primary hyperparathyroidism.

RET haplotype, not linked to the C620R activating mutation, associated with Hirschsprung disease in a novel MEN2 family

Hirschsprung disease is a congenital form of aganglionic megacolon that results from cristopathy. Hirschsprung disease usually occurs as a sporadic disease, although it may be associated with several inherited conditions, such as multiple endocrine neoplasia type 2. The rearranged during transfection (RET) proto-oncogene is the major susceptibility gene for Hirschsprung disease, and germline mutations in RET have been reported in up to 50% of the inherited forms of Hirschsprung disease and in 15-20% of sporadic cases of Hirschsprung disease. The prevalence of Hirschsprung disease in multiple endocrine neoplasia type 2 cases was recently determined to be 7.5% and the cooccurrence of Hirschsprung disease and multiple endocrine neoplasia type 2 has been reported in at least 22 families so far. It was initially thought that Hirschsprung disease could be due to disturbances in apoptosis or due to a tendency of the mutated RET receptor to be retained in the Golgi apparatus. Presently, there is strong evidence favoring the hypothesis that specific inactivating haplotypes play a key role in the fetal development of congenital megacolon/Hirschsprung disease. In the present study, we report the genetic findings in a novel family with multiple endocrine neoplasia type 2: a specific RET haplotype was documented in patients with Hirschsprung disease associated with medullary thyroid carcinoma, but it was absent in patients with only medullary thyroid carcinoma. Despite the limited number of cases, the present data favor the hypothesis that specific haplotypes not linked to RET germline mutations are the genetic causes of Hirschsprung disease.

The Hirschsprung's-multiple endocrine neoplasia connection

The risk of patients with Hirschsprung's disease later developing multiple endocrine neoplasia remains a matter of concern. The multiple endocrine neoplasia 2-Hirschsprung's disease association has been shown to cosegregate in Hirschsprung's disease patients with both short- and long-segment aganglionosis, although patients with long-segment aganglionosis a to carry the greatest risk. The Hirschsprung's disease-medullary thyroid carcinoma relationship also appears to be bi-directional, and activation or suppression of the rearranged during transfection gene appeared to vary over succeeding generations within the same family. Rearranged during transfection gene variations are associated with both conditions. The cosegregation of Hirschsprung's disease and multiple endocrine neoplasia 2 is particularly interesting as it involves both "switch off" and "switch on" of the rearranged during transfection proto-oncogene in the same patient. This cosegregation mostly relates to the cysteine-rich area on RET620 (the "Janus gene"). The mechanism whereby rearranged during transfection influences gene activation in multiple endocrine neoplasia 2 is complex, but genetic variations impair the rearranged during transfection tyrosine kinase response to tyrosine kinase activation, thus appearing to dictate downstream signaling cascade responses. Better understanding of the RET-620 relationship allows for a more cost-effective method of identifying those at risk by focusing rearranged during transfection gene testing to this specific area as a "hot spot". The clinical awareness of possible medullary thyroid carcinoma has led to timely intervention and early treatment of this chemo- and radioresistant tumor with poor prognosis. Establishment of "risk" by genetic testing has become a classic model of molecular medicine being integrated into patient care and offering rearranged during transfection directed prophylactic surgical management. In addition, novel approaches to treatment based on this genetic knowledge have already shown early promise in randomized clinical trials.

Genotype-phenotype correlation in multiple endocrine neoplasia type 2

Multiple endocrine neoplasia type 2 is an autosomal-dominant hereditary cancer syndrome caused by missense gain-of-function mutations of the rearranged during transfection proto-oncogene, which encodes the receptor tyrosine kinase, on chromosome 10. It has a strong penetrance of medullary thyroid carcinomas and can be associated with bilateral pheochromocytoma and primary hyperparathyroidism. Multiple endocrine neoplasia type 2 is divided into three varieties depending on its clinical features: multiple endocrine neoplasia type 2A, multiple endocrine neoplasia type 2B, and familial medullary thyroid carcinoma. The specific rearranged during transfection mutation may suggest a predilection toward a particular phenotype and clinical course of medullary thyroid carcinoma, with strong genotype-phenotype correlations. Offering rearranged during transfection testing is the best practice for the clinical management of patients at risk of developing multiple endocrine neoplasia type 2, and multiple endocrine neoplasia type 2 has become a classic model for the integration of molecular medicine into patient care. Recommendations on the timing of prophylactic thyroidectomy and extent of surgery are based on the classification of rearranged during transfection mutations into risk levels according to genotype-phenotype correlations. Earlier identification of patients with hereditary medullary thyroid carcinoma can change the presentation from clinical tumor to preclinical disease, resulting in a high cure rate of affected patients and a much better prognoses.